4. Going back to the dog whistle in question 1, what is the minimum riding speed needed to be able to hear the whistle? Remember, you can assume the following things: The whistle you use to call your hunting dog has a frequency of 21.0 kHz, but your dog is ignoring it. You suspect the whistle may not be working, but you can't hear sounds above 20.0 kHz. The speed of sound is 330 m/s at the current air temperature.

Answer:

Explanation:

According to newton's third law of motion, Action and reaction are equal and opposite, hence for an object that weighs 150N suspended by a wire, the tension on the wire is 150N

Ultimately the tension on a string or an object is equal to the mass times   gravity(which is same as the weight of the object)

Answer:

its 150

Explanation:

Answer:

15.96 m³ (corrected to 2 d.p.)

Explanation:

Using idea gas law:

pV = nRT

pressure p = 125000 Pa

volume V = unknown

no. of moles n= 3.27 moles

ideal gas constant R = 8.3145 J K−1 mol−1

Temperature t (in Kelvins) = 15 + 273.15 = 288.15K

125000 x v = 3.27 x 8.3145 x 288.15

v = 15.96 m³ (corrected to 2 d.p.)

Answer:

0.0626 m^3

Explanation:

First, we know that the equation to calculate the behavior of gases is:

PV=nRT

Looking at the problem, we understand that we are needing to solve for V, which means we need to isolate V to solve for it.

The new equation will look something like this:

V=nRT/P

The last step is to simply plug in the remaining variables:

n=3.27

R=8.31 (that is not given but is a standard number that you will always use for "R"/ the ideal gas constant-it helps to right it down somewhere to reference it if you ever need it!)

P=125000

T=288 (the temp needs to be in degrees K, so take 15.0 degrees c and + 273)

Finally, when you input all of those, you will have something that looks like this:

V=(3.27*8.31*288)/125000

V=0.02608205 m^3

V= 0.0626 m^3 (rounded to 3 sig. figs)

I hope this was helpful and easy to understand!

Answer:

1.25x10^-19N

Explanation:see attached file pls

Answer:

900 cm/s or 9 m/s.

Explanation:

Data obtained from the question include the following:

Length (L) = 30 cm

frequency (f) = 60 Hz

Velocity (v) =.?

Next, we shall determine the wavelength (λ).

This is illustrated below:

Since the wave have 4 node, the wavelength of the wave will be:

λ = 2L/4

Length (L) = 30 cm

wavelength (λ) =.?

λ = 2L/4

λ = 2×30/4

λ = 60/4

λ = 15 cm

Therefore, the wavelength (λ) is 15 cm

Now, we can obtain the speed of the wave as follow:

wavelength (λ) = 15 cm

frequency (f) = 60 Hz

Velocity (v) =.?

v = λf

v = 15 × 60

v = 900 cm/s

Thus, converting 900 cm/s to m/s

We have:

100 cm/s = 1 m/s

900 cm/s = 900/100 = 9 m/s

Therefore, the speed of the wave is 900 cm/s or 9 m/s.

Answer:

v = 14.32 m/s

Explanation:

According to the principle of conservation of linear momentum, both the momentum and kinetic energy of the system are conserved. Since the two balls are in the same direction of motion before collision, then;

[tex]m_{1} u_{1}[/tex] + [tex]m_{2} u_{2}[/tex] = ([tex]m_{1}[/tex] + [tex]m_{2}[/tex]) v

0.035 × 12 + 0.120 × 15 = (0.035 + 0.120) v

0.420 + 1.800 = (0.155) v

2.22 = 0.155 v

⇒ v = [tex]\frac{2.22}{0.155}[/tex]

      = 14.323

The velocity of the balls after collision is 14.32 m/s.

Answer:

0.66c

Explanation:

Use length contraction equation:

L = L₀ √(1 − (v²/c²))

where L is the contracted length,

L₀ is the length at 0 velocity,

v is the velocity,

and c is the speed of light.

900 = 1200 √(1 − (v²/c²))

3/4 = √(1 − (v²/c²))

9/16 = 1 − (v²/c²)

v²/c² = 7/16

v = ¼√7 c

v ≈ 0.66 c

Answer:

some common devices that use current carrying conductors and magnetic fields are electric motor electric generator loudspeakers microphones and measuring instruments like galvanometer ammeter and voltmeter

Explanation:

Things you need to know:

Accuracy refers to the maximum error encountered when a particular observation is made.

Error in measurement is normally one-half the magnitude of the smallest scale reading.

Because one has to align one end of the rule or device to the starting point of the measurement, the appropriate error is thus twice that of the smallest scale reading.

Error is usually expressed in at most 1 or 2 significant figures.

Tape

Equipment: It is made up of a long flexible tape and can measure objects or places up to 10 – 50 m in length. It has markings similar to that of the rigid rule. The smallest marking could be as small as 0.1 cm or could be as large as 0.5 cm or even 1 cm.

How to use: The zero-mark of the measuring tape is first aligned flat to one end of the object and the tape is stretched taut to the other end, the reading is taken where the other end of the object meets the tape.

Ruler

Equipment: It is made up of a long rigid piece of wood or steel and can measure objects up to 100 cm in length. The smallest marking is usually 0.1 cm.

How to use: The zero-end of the rule is first aligned flat with one end of the object and the reading is taken where the other end of the object meets the rule.

Vernier Caliper

Equipment: It is made up of a main scale and a vernier scale and can usually measure objects up to 15 cm in length. The smallest marking is usually 0.1 cm on the main scale.

It has:

a pair of external jaws to measure external diameters

a pair of internal jaws to measure internal diameters

a long rod to measure depths

How to use: The jaws are first closed to find any zero errors. The jaws are then opened to fit the object firmly and the reading is then taken.

Micrometer Screw Gauge

Equipment: It is made up of a main scale and a thimble scale and can measure objects up to 5 cm in length. The smallest marking is usually 1 mm on the main scale (sleeve) and 0.01 mm on the thimble scale (thimble). The thimble has a total of 50 markings representing 0.50 mm.

It has:

an anvil and a spindle to hold the object

a ratchet on the thimble for accurate tightening (prevent over-tightening)

How to use: The spindle is first closed on the anvil to find any zero errors ( use the ratchet for careful tightening). The spindle is then opened to fit the object firmly (use the ratchet for careful tightening) and the reading is then taken.

Answer:

The patient is suffering from protein deficiency

Explanation:

Protein deficiency is characterized by symptoms such as stunted growth; skin, nail and hair problems, loss of muscle mass, and in extreme cases, kwashiorkor.

Deficiency in protein is usually corrected by taking foods rich in protein such as egg's albumin, milk, pulses, beans, etc; hence the advice of the doctor.

Answer:

[tex]f^{-1}(-4) = \frac{1}{10}[/tex]

Explanation:

Firstly finding [tex]f^{-1}(x)[/tex]

So,

[tex]f(x) = 10x-5[/tex]

Substitute [tex]y = f(x)[/tex]

[tex]y = 10x-5[/tex]

Exchange the values of x and y

[tex]x = 10y-5[/tex]

Solving for y

[tex]x = 10y-5[/tex]

Adding 5 to both sides

[tex]10y = x+5[/tex]

Dividing both sides by 10

[tex]y = \frac{x+5}{10}[/tex]

Replace [tex]y = f^{-1}(x)[/tex]

[tex]f^{-1}(x) = \frac{x+5}{10}[/tex]

For x = -4

[tex]f^{-1}(-4) = \frac{-4+5}{10}[/tex]

[tex]f^{-1}(-4) = \frac{1}{10}[/tex]

Answer:

[tex]\frac{1}{10}[/tex]

Explanation:

f(x) = y (output)

y = 10x - 5

Switch variables.

Solve for y.

x = 10y - 5

x + 5 = 10y

x/10 + 1/2 = y

[tex]f^{-1}(x)[/tex] = 1/10x + 1/2

Put x as -4.

1/10(-4) + 1/2

-4/10 + 1/2

-4/10 + 5/10

= 1/10

Explanation:

Because of air pressure

Answer:

Explanation:

The range of mercury thermometer is - 37°C to 356°C . At temperature below - 37°C , mercury starts converting into solid so this thermometer becomes non-  functional . Hence to measure temperature of - 50°C , alcohol thermometer is suitable . The range of alcohol thermometer is - 112° C to 78°C .  

Answer: 17cm.

Explanation:

The equation you're using is:

Δd = df - di

Which means the change in position is equal to the final position minus the starting position. In this case that works out to 20cm - 3cm = 17cm. We're only interested in how much the snail moved, not how long it took to move, so even though they give a time it actually doesn't matter for this question.

Answer:

(d) Water has a high specific heat.

Explanation:

At night, when the temperature of earth goes down due to loss of heat , the temperature of water is lost slowly and temperature of land is lost fast because of high specific heat of water . Water loses as well as gains temperature comparatively slowly due to its high specific heat .

During daytime when earth gains heat , the temperature of land rises more rapidly than water so water appears cool even during daytime when land becomes  hotter . It is also due to high heat holding capacity of water or due to high specific heat of water .

Answer:

Explanation: Let assume that bars are labeled A and B

Method 1

Using just the identical appearing bar magnet and unmagnetized iron bar.

Place the end of bar A in the middle of bar B.

If bar A sticks to bar B, then bar A is the magnet and bar B the umagnetized iron bar.

If bar A jumps to one of the ends of bar B, then bar B is the magnet.

Reason been that the magnetic field on a bar magnet is greatest at the two poles where the field comes out of the magnet. The center, between the poles, will be the weakest part of the field.

Method 2

Another solution would be to separate the two by quite some distance, float them on a piece of cork/wood in a plastic bucket or suspend them from long strings, then see which one consistently (eventually) lines up tending towards the Earth’s magnetic field.

Answer:

16 m

Explanation:

Given:

v₀ = 4 m/s

a = 4 m/s²

t = 2 s

Find: Δx

Δx = v₀ t + ½ at²

Δx = (4 m/s) (2 s) + ½ (4 m/s²) (2 s)²

Δx = 16 m

Answer:

175 m

Explanation:

Given:

y = 220 m

v₀ = 30 m/s

v = 0 m/s

a = -10 m/s²

Find: y₀

v² = v₀² + 2a (y − y₀)

(0 m/s)² = (30 m/s)² + 2 (-10 m/s²) (220 m − y₀)

y₀ = 175 m

Answer:

Explanation:

A ) Let the angle be θ between magnetic field and velocity of charged particle

Force created on charged particle F

= Bqv sinθ, B is magnetic field , q is charge , v is velocity of charged particle

F = .05 x 2 x 10⁻⁶ x 10⁸ x sinθ

8 = 10 sinθ

sinθ = .8

θ =  53°.

B )

acceleration = force / mass

= 8 / 10⁻²⁰

= 8 x 10²⁰ m / s²

Answer:

3.6ft

Explanation:

Using= 2*π*sqrt(L/32)

To solve for L, first move 2*n over:

T/(2*π) = sqrt(L/32)

Next,eliminate the square root by squaring both sides

(T/(2*π))2 = L/32

or

T2/(4π2) = L/32

Lastly, multiply both sides by 32 to yield:

32T2/(4π2) = L

and simplify:

8T²/π²= L

Hence, L(T) = 8T²/π²

But T = 2.1

Pi= 3.14

8(2.1)²/3.14²

35.28/9.85

= 3.6feet

Answer:

The direction of the acceleration of the mass is due East.

Explanation:

Data obtained from the question include the following:

Mass = 5 kg

Force due South = 10 N.

Force due East = 15 N.

To know which direction the acceleration of the mass will go, we must first obtain the resultant force.

This is illustrated below:

Resultant force = 15 – 10 = 5 N

Therefore, the resultant force is 5 N due East since the larger force is due East

Since the resultant force is due East, it means that the mass will accelerate toward the East.

According to the question,

The resultant force will be:

= [tex]15-10[/tex]

= [tex]5 \ N[/tex]

Since the larger force is due east. Thus the answer above is right.

Learn more about force here:

https://brainly.com/question/1844505

Answer:

The correct answer is "By increasing the amount of flooding because of rising sea levels".

Explanation:

I think any pendulum would swing slower on the moon than it would on Earth.

The time it takes a pendulum to go through a complete back and forth swing is:

Time period = 2 π √(length/gravity)

You can see that 'gravity' is in the denominator of the fraction, so the smaller gravity gets, the longer the period gets.

To be a little bit more technical, the period is inversely proportional to the square root of gravity.

So the period for a complete swing on the moon would be  √(9.8/1.6) times as long as the complete swing of the same pendulum on Earth.

That number is roughly 2.47 .

So, for every 1 second that a pendulum takes to swing back and forth once on Earth, the same pendulum would take 2.47 seconds to do it on the moon.

Answer:

based on my opinion....

as we know that gravity in moon are less than gravity in earth.. since the force of gravity is less on the moon, the pendulum would swing slower at the same length, angle

and the frequency would be less.

I hope this helps

Explanation:

Boyles law is the pressure of a fixed mass of gas which is inversely proportional to its volume provided that the temperature is kept constant.

Answer:

h = 10000 m

Explanation:

The pressure applied at a depth of the liquid is given by:

P =ρgh

where,

P = Maximum Pressure to Survive = (1000)(Atmospheric Pressure)

P = (1000)(101325 Pa) = 1.01 x 10⁸ Pa

ρ = Density of sea water = 1025 kg/m³

g = 9.8 m/s²

h = maximum depth to survive = ?

Therefore,

1.01 x 10⁸ Pa = (1025 kg/m³)(9.8 m/s²)h

h = (1.01 x 10⁸ Pa)/(1025 kg/m³)(9.8 m/s²)

h = 10000 m

Answer:

likely to decrease downstream in arid regions and increase downstream in temperate regions

Explanation:

Arid regions are is a region with a severe lack of water, usually to the extent that affect the organisms living in the region. Arid regions are characterized by a very low depth of rainfall per year. Temperate region on the other hand experience more distinct seasonal change and wider temperature change. Temperate regions get a fairly large amount of rainfall per year.

In arid regions, the soil is very dry, and the rate of infiltration and percolation is high relative to the amount of rainfall available. The effect is that more water is infiltrated into the soil as you move downstream, leading to a decrease in the discharge of a stream as you move downstream. Most temperate region have soils that are usually saturated in the peak of the rainfall season, leading to a greater stream discharge as you move downstream.  

Answer:

it is used because

They are also less likely to jam due to rust in the screw thread.

Hydraulic jacks are often used to lift elevators in low and medium rise buildings.

A hydraulic jack uses a liquid that is forced into a cylinder by a pump plunger.

Answer:

C

Explanation:

Answer:

c. A dog of mass 14 kg running with speed 6 m/sation:

Answer:

a) -1.25 m/s²

b) 62.5 m

Explanation:

Convert km/h to m/s:

45 km/h × (1000 m/km) × (1 h / 3600 s) = 12.5 m/s

a = Δv / Δt

a = (0 m/s − 12.5 m/s) / 10 s

a = -1.25 m/s²

Δx = ½ (v + v₀) t

Δx = ½ (0 m/s + 12.5 m/s) (10 s)

Δx = 62.5 m

Answer:

8.8 mT

Explanation:

Current through the conductor = 12.5 A

Magnetic force per unit length on the wire = 0.110 N/m

Recall that the magnetic force per unit length on a current carrying conductor is in a uniform magnetic field is

[tex]\frac{F}{l}= IBsin\alpha[/tex]

where B is the magnetic field magnitude

[tex]I[/tex] is the current in the conductor

α is the angle the conductor makes with the  magnetic field ( since it is perpendicular in this case, α is 90°)

imputing values into the equation, we'll have

0.11 = 12.5 x B x sin 90°

but sin 90° = 1, therefore, we have

0.11 = 12.5B

B = 0.11/12 = 8.8 x 10^-3 T

or rather = 8.8 mT

Answer:

Explanation:

Load ( L ) = 500 N

Effort ( E ) = 200 N

Load distance ( LD ) = 3 m

Effort distance ( ED ) = ?

Now, Let's find the Effort distance ( ED )

We know that,

Output work = Input work

i.e L × LD = E × ED

plug the values

[tex]500 \times 3 = 200 \times ED[/tex]

multiply the numbers

[tex]1500 = 200 \times ED[/tex]

Swipe the sides of the equation

[tex]200 \: ED \: = 500[/tex]

Divide both sides of the equation by 200

[tex] \frac{200 \: ED}{200} = \frac{500}{200} [/tex]

Calculate

[tex]ED\: = 2.5 \: m[/tex]

Hope this helps..

best regards!!